Tinea capitis is an infestation caused by fungal action that affects the scalp, with a propensity to attack the hair shaft and follicles. It is considered a form of superficial mycosis or dermatophytosis, also known as scalp ringworm and tinea tonsurans.
In some countries, the incidence of tinea capitis is increasing and affects prepubescent children aged 3 to 10 years, more boys than girls. It can also affect postmenopausal adults caring for young children.
How does it manifest itself?
It is most commonly found in urban areas and is manifested by the presence of scaly, itchy skin rashes, a scald with hair loss or, in some cases, both.
While Microsporum canis is the most common cause of cases in Europe, especially in countries bordering the Mediterranean, Trichophyton tonsurans is described as “highly prevalent” in other regions of Europe, with50-90% of diagnoses reported.
The first, Microsporum canis, is a fungus that can infect the upper layers of the skin of cats or domestic dogs, but can also be found on the skin of humans, being in fact largely transmitted by animals, particularly puppies.
In the last 50 years, the predominant etiologic agent of tinea capitis in Europe and other countries of the world has changed from Microsporum audouinii to Trichophyton tonsurans. It is believed that this is due in part to the sensitivity of the former to treatment with griseofulvin and in part to the importation of the latter, the tonsurans, by some people migrating from geographical areas where that vector had been the main cause of tinea capitis.
As a result of these changes, new prospects for therapy based on antifungal agents such as itraconazole, fluconazole, and terbinafine arise.
The two clinical forms of tinea capitis
There are two clinical forms of ringworm of the scalp:
- Inflammatory: plaques of alopecia erythematosus with scaly lesions, pustular folliculitis, and purulent nodules may be observed. These lesions are accompanied bypruritus, painful areas, local and regional lymphadenopathy, fever, and hypersensitivity reactions.
- Noninflammatory: is the more common of the two and, as the name suggests, is characterized by the absence of an inflammatory reaction or the minimal presence of one. Squamous lesions, “black spot” dermatophytosis with an associated fragility of the hair shaft are present.
Seborrheic dermatitis, atopic dermatitis, and psoriasis are very similar in their clinical presentation. Direct examination with 30% KOH and mycological culture (Sabouraud agar) confirm whether dermatophytosis is correct. Sampling may be a suitable procedure for children, where brushing the lesion is more tolerable than a scalpel or tweezers.
Tinea capitis is usually treated with antifungal, oral or topical short term therapies, usually for a few weeks on a daily basis.
Some of the most popular options include ketoconazole oral or selenium sulfide shampoo and miconazole antifungal cream. The choice of dose and frequency of use will be determined by the prescribed treatment based on factors such as age and general health.
If left untreated, some cases may lead to the development of a permanent alopecia condition or even cause further diffusion of the infection.